I want life to be boring, says Linus Torvalds as Linux 4.15 debuts

But Linux overlord braces for more Meltdown/Spectre excitement as kernelistas clean up remaining CPU messes

Linus Torvalds has hit the Go button on version 4.15 of the Linux kernel, blaming the Meltdown and Spectre CPU design flaws for the delay and warning of more pain to come as fixes trickle out for silicon architectures.

“This obviously was not a pleasant release cycle, with the whole meltdown/spectre thing coming in in the middle of the cycle and not really gelling with our normal release cycle,” Torvalds wrote.

“The extra two weeks were obviously mainly due to that whole timing issue.”

“Also, it is worth pointing out that it's not like we're ‘done’ with spectre/meltdown,” Torvalds added. “There is more work pending (arm, spectre-v1, misc details), and perhaps equally importantly, to actually get the biggest fix for the indirect branch mitigations, you need not just the kernel updates, you need to have a compiler with support for the ‘retpoline’ indirect branch model.”

“You can do
cat /sys/devices/system/cpu/vulnerabilities/spectre_v2
and if you don't have a compiler that supports the retpoline mitigations, you'll get: Vulnerable: Minimal generic ASM retpoline because only the assembly code (not the C code) will have the retpoline mitigation. So keep that in mind.”

We will, Linus, we will.

And then we’ll contemplate all the goodies in Linux 4.15, which Torvalds wrote is mostly “the regular plodding ‘boring’ stuff.”

“And I mean that in the best possible way. It may not be glamorous and get the headlines, but it's the bread and butter of kernel development, and is in many ways the really important stuff.”

The big boring in this release is extensive support for AMD GPUs, and full support for graphics in Intel’s Coffee Lake architecture.

The kernel now also supports networking over Thunderbolt cables, has added a few features to make NVMe smoother and brought RAID 10 to Linux Soft RAID. Another addition is a USB type C port manager.

As ever, Linus has opened a merge Window for the next version of the kernel, and has expressed his hope that nothing interesting appears during that period, or indeed during the next few weeks.

“Hopefully we'll have a _normal_ and entirely boring release cycle for 4.16,” he wrote, “Because boring really is good.” ®